Dust-collecting hopper and cooling hood for converters



July 27, 1965 R. F. MIRIGAY DUST-COLLECTING HOPPER AND COOLING HOOD FOR CONVERTERS Filed April 3, 1962 2 Sheets-Sheet 1 Fig-l 19 25 ii :Z: 18 I 17;:- f

g l 26 zs 30 1 I 24, T' -26 24 29 25b 9 Z Z8 July 27, 1965 R. F. MIRIGAY $3,

DUST-COLLECTING HOPPER AND COOLING HOOD FOR CONVERTERS Filed April 3, 1962 2 Sheets-Sheet 2 United States Patent 3,197,186 DUST-COLLECTING HOPPER AND COOLING HOOD FOR CONVERTERS Rene Francis Mirigay, Ville dAvray, France, assignor to Stein & Roubaix, Socite Anonyme, Paris, France, a

company of France Filed Apr. 3, 1962, Ser. No. 184,844 (Ilaims priority, application France, Apr. 11, 1961,

2 Claims. (c1. 266-15) The gases which emerge from converters and particularly from oxygen-blown converters, contain considerable quantities of dust that can be strongly prejudicial to the neighbourhood of the steelworks. For this reason the gases must be cleansed of dust before they are discharged into the atmosphere. They must therefore be collected as they issue from the vessel, steps taken to ensure the combustion of the very large proportion of combustible elements they contain, and the gases finally cooled. Collecting of the gases, their combustion and part of their cooling process are generally ensured by means of a hood disposed above the converter.

This invention relates to a hood of which the walls are cooled by water turning into steam, the heat being evacuated through the medium of steam discharged into the atmosphere or through low pressure steam.

The description which follows with reference to the accompanying drawings, filed by way of example only and not of limitation, will give a clear understanding of how the invention may be carried into practice.

Referring to the drawings filed herewith:

FIG. 1 is a general-arrangement view of the hood according to the invention;

FIG. 2 is a simplified plan view of the lower part of the hood; and

FIG. 3 is a sectional view of the upper part of the hood.

In the embodiment of the hood illustrated by way of example in the accompanying drawings, the converter 1 has disposed above it a hood which comprises a front spout or hopper forming a cylindrical surface 2 of polygonal and preferably regular octagonal cross-section, which is bounded at its lower end by a plane 3 closely spaced from the plane of the converter outlet lip 30, and at its upper end by a horizontal plane 4. The collecting spout allows for a regular gap between it and the periphery of the converter outlet lip, thereby allowing for suction of the air 5 needed for the combustion of the gas issuing from the vessel with a minimum of excess air. The collecting spout is extended by an inclined spout 6 of roughly frusto-pyramidal shape which is joined to the surface 2 over the plane 4. The inclination of spout 6 is chosen in such manner as to permit rapid disengagement of the oxygen blowing pipe 7, and its length to provide sufiicient clearance above the converter to allow conducting the additional products to be introduced into the converter during operation, and also for possible repairs to the bricking used for the vessel.

The hood spout 6 is followed by a likewise polygonal and preferably regular octagon-shaped chimney 8 which is joined to said spout 6 over the horizontal plane 9. The height of this chimney is chosen so that, when the gases reach its top, they should be sufficiently cooled by radiation to enable them to be subsequently cooled in a heat exchanger by convection or conveniently conveyed to a final cooling and conditioning installation before the dust extraction process. The gas is conducted to this installation through the duct 10.

Level with the chimney 8, at the bottom thereof, the hood comprises a hopper 11 of polyhedral general shape, adapted to collect the projections from the vessel 1 and such deposits as may collect in the chimney 8 and become detached during the heating and cooling processes consecutive to each operation. Such extraneous matter collected in the hopper is discharged through the orifice 12.

The faces which bound the surfaces 2, 6, 8 and 11 consist of flat double-walled panels providing an internal circulation of vaporizing water. These panels are easy to dismantle from Within, to permit maintenance, repairs or replacements should the need arise.

The chimney 8 is surmounted by an emergency chim ney 13 of circular section which is united to it through the medium of a frusto-conical skirt 14. The free section between the circular base of the skirt and the upper polygonal section is closed in by means of metal sheeting 15. The upper portion of the chimney 13 is occulded by a normally-closed clapper 16 which opens in the event of a malfunctioning of the gas conditioning and dedusting installation disposed downstream of the hood. The interior of the chimney 13 and the skirt 14 are lined with refractory material; since this part of the installation is used only under emergency conditions and is crossed by the previously cooled gases, it need not be water-cooled.

In accordance with this invention, the water-steam emulsion separating tank 17 is installed about the chimney 13, as is illustrated by way of example in FIGURE 1. This tank is annularly shaped and the internal circumference of the tank is constituted by a cylindrical portion of the chimney 13 and by the frusto-conical skirt 14. The outer part of said tank consists of a frusto-conical section 18 and a cylindrical section 19. The top of the tank is closed by a frusto-conical roof 20 which is so disposed as to leave an annular space 21 between it and the cylindrical section 19 to allow the steam to discharge into the atmosphere. Should it be desired to recover the steam produced, the spaces 21 would be eliminated and steam ducts installed in the roof 20. An access door into the tank is provided in the roof 20 at 22. The water-steam emulsion from the panels constituting the faces of chimney 8 is conveyed to the tank 17 through a system of pipes 23. The water supplying the cooling surfaces 2, 6, 11 and 8, after it has been separated from the steam, is led down through a system of pipes 24 arranged along the periphery of the tank 17, preferably at the corners of the polygon forming the chimney 8, in order to avoid overcrowding of the passageway for the discharge pipes 23.

One of the essential characteristics of the invention consists in using the downleading pipes 24 as the main members of a structure which serves, on the one hand, to sup port the tank 17 and the chimney 13 and, on the other hand, to support and guide the panels constituting the surfaces 2, 6, 11 and 8. To this end, the pipes 24 are crossbraced by cages 25 and stiffeners 26. The cages 25 and the stiffeners 26 consist of tubes which are disposed in and are crossed by the water descending through the tank towards the bottom of the panels, in such manner that the assembly forms, with the downleading pipes 24, a rigid system adapted to support the tank and the chimney and to guide and support the pannels constituting the faces of the hood, the system being of uniform temperature throughout, i.e. at the temperature of the descending water, and being free to expand. The panels are supplied from the bottommost cage 25a through pipes such a 27. The tubular structure reposes at the level of cage 25b on a support 28 forming part of the steelworks building, the manner of attachment being adapted to permit free expansion of the tubular structure.

The panels are rigidly supported by the tubular structure at the level of cage 25b by support 29. At the levels of the other girdles the panels are attached to the tubular structure merely by staple means allowing them to expand freely relative to the structure. By way of example, FIG. 3 illustrates the manner of attachment of the panels to the tubular structure at the level of a cage 25 encircling the chimney 8. The sliding attachment means referred to 3,197,185 Patented July 27, 1965 hereinbefore are denoted by the reference numeral 39.

What is claimed is:

1. A hood for cooling waste gases from a converter, comprising an inclined spout portion of generally frustopyramidal shape; a substantially vertical chimney portion of polygonal cross-section surmounting aid inclined spout portion; a polyhedron-shaped hopper portion for collecting dust carried by said waste gases and disposed beneath and substantially aligned with said chimney portion, said portions being formed from flat panels constituted by double walls through which cooling water may be circulated; an emergency chimney mounted atop said chimney portion and having a lined, uncooled Wall; a clapper port-ion in said emergency chimney normally closing the same against passage of said waste gases therethrough; a shell surrounding said emergency chimney spaced therefrom and forming with the wall thereof a tank of substantially toroidal shape; a plurality of downwardly extending pipes for conveying water from said tank toward the lower part of said hood, connecting means for placing said pipes in communication with the space comprised between the double walls of said panels, cross-bracing first tubes interconnecting said pipes, and second tubes extending transversely of said pipes and interconnecting the same in such manner that said pipes form in conjunction with said cross-bracing first tubes and said second tubes the supporting structure for said hood.

' 2. An arrangement of the character described for cooling waste gases from a converter comprising, in combination, a hood including an inclined spout portion of generally frusto-pyramidal shape, a substantially vertical chimney portion of polygonal cross-section surmounting said inclined spout portion, and a polyhedron-shaped hopper portion for collecting dust carried by said Waste gases and disposed beneath and substantially aligned with said chimney portion, said portions being formed from flat panels constituted by double walls defining a free space therebetween through which cooling water may be circulated; a water tank mounted on top of said hood; a first plurality of pipes extending spaced from each other longitudinally along said portions of said hood and respectively communicating at the upper ends thereof with said water tank and at the lower ends thereof with said spout and said hopper portions; a second plurality of pipes extending transverse to said first plurality of pipes connected to and communicating with the latter, said pipes forming a cage around said hood closely adjacent to the outer surface thereof; support means operatively connected to said cage for supporting the same; and cooperating means on said cage and on said hood for supporting the latter on said cage while permitting different heat expansion of cage and hood.

References Cited by the Examiner UNITED STATES PATENTS 178,562 6/76 Renwick et al 189-12 1,035,431 8/12 Ericson 18912 1,066,225 7/13- Roberts et al. 266-31 2,040,532 5/36 Rice 266--31 2,847,206 8/58 McFeaters 266-35 FOREIGN PATENTS 824,955 12/51 Germany.

OTHER REFERENCES German printed application, 1,032,291, June 1958. German printed application, 1,064,971, September 1959.

MORRIS O. WOLK, Primary Examiner.

JAMES H. TAYMAN, JP, Examiner. 

1. A HOOD FOR COOLING WASTE GASES FROM A CONVERTER, COMPRISING AN INCLINEED SPOUT PORTION OF GENERALLY FRUSTOPYRAMIDAL SHAPE; A SUBSTANTIALLY VERTICAL CHIMNEY PORTION OF POLYGONAL CROSS-SECTION SURMOUNTING SAID INCLINED SPOUT PORTION; A POLYHEDRON-SHAPED HOPPER PORTION FOR COLLECTING DUST CARRIED BY SAID WASTE GASES AND DISPOSED BENEATH AND SUBSTANTIALLY ALIGNED WITH SAID CHIMNEY PORTION, SAID PORTIONS BEING FORMED FROM FLAT PANELS CONSTITUTED BY DOUBLE WALLS THROUGH WHICH COOLING WATER MAY BE CIRCULATED; AN EMERGENCY CHIMNEY MOUNTED ATOP SAID CHIMNEY PORTION AND HAVING A LINED, UNCOOLED WALL; A CLAPPER PORTION IN SAID EMERGENCY CHIMNEY NORMALLY CLOSING THE SAME AGAINST PASSAGE OF SAID WASTE GASES THERETHROUGH; A SHELL SURROUNDING SAID EMERGENCY CHIMNEY SPACED THEREFROM AND FORMING WITH THE WALL THEREOF A TANK OF SUBSTANTIALLY TOROIDAL SHAPE; A PLURALITY OF DOWNWARDLY EXTENDING PIPES FOR CONVEYING WATER FROM SAID TANK TOWARD THE LOWER PART OF SAID HOOD, CONNECTING MEANS FOR PLACING SAID PIPES IN COMMUNICATION WITH THE SPAKCE COMPRISED BETWEEN THE DOUBLE WALLS OF SAID PANELS, CROSS-BRACING FIRST TUBES INTERCONNECTING SAID PIPES, AND SECOND TUBES EXTENDING TRANSVERSELY OF SAID PIPES AND INTERCONNNECTING THE SAME IN SUCH MANNER THAT SAID PIPES FORM IN CONJUNCTION WITH SAID CROSS-BRACING FIRST TUBES AND SAID SECOND TUBES THE SUPPORTING STRUCTURE FOR SAID HOOD. 